<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <!-- 反转字符串
    var str = 'abcdefg'

 要求结果
 gfedcba -->
    <script>
      var str = "abcdefg";
      var res = str.split("").reverse().join("");
      console.log(res);
    </script>
  </body>
</html>
